psi

[ sahy, psahy ]

/ saɪ, psaɪ /

noun, plural psis.

the 23rd letter of the Greek alphabet (Ψ, ψ).

the group of consonant sounds represented by this letter.

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Origin of psi

1350–1400; Middle English < Greek pseî

Words nearby psi

pseudovector, pseudoxanthoma elasticum, psf, psg, pshaw, psi, psi particle, psi phenomenon, psia, psid, psig

Definition for psis (2 of 2)

psi²

[ sahy ]

/ saɪ /

noun

any purportedly psychic phenomenon, as psychokinesis, telepathy, clairvoyance, or the like.

Compare pseudoscience, parapsychology.

Origin of psi

1940–45; shortening of psychic or parapsychic

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for psis

"I thought you'd welcome a reputable attorney who would represent Psis," I reminded him.
Modus Vivendi|Gordon Randall Garrett
Pheola of the race-horse legs joined us, and several other psis as well.
Card Trick|Walter Bupp AKA Randall Garrett
Their attire, their homes, everything about Psis, seems tasteful.
Modus Vivendi|Gordon Randall Garrett
But I will never believe that Psis would permit themselves to be represented by a Normal.
Modus Vivendi|Gordon Randall Garrett

It's understood wherever people gamble that psis aren't welcome.
Card Trick|Walter Bupp AKA Randall Garrett

British Dictionary definitions for psis (1 of 3)

PSIS

abbreviation for (in New Zealand)

Public Service Investment Society, New Zealand's largest credit union

British Dictionary definitions for psis (2 of 3)

psi¹

abbreviation for

pounds per square inch

British Dictionary definitions for psis (3 of 3)

psi²

/ (psaɪ) /

noun

the 23rd letter of the Greek alphabet (Ψ, ψ), a composite consonant, transliterated as ps

paranormal or psychic phenomena collectively
(as modifier)psi powers

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for psis

psi

[ sī, psī ]

n.

The 23rd letter of the Greek alphabet.